Effect of Toothpaste With Trimetaphosphate Nano-sized on the Enamel Remineralization

Objectives: This study evaluated the remineralizing effects of conventional toothpastes (1100 ppm F) associated or not with micrometric or nano-sized TMP using an in situ model and artificially demineralized bovine enamel blocks.
Methods: This blind and cross-over study was performed in 4 phases of 3 days each. Twelve subjects used palatal appliances containing four bovine enamel blocks with artificial caries lesions. Methods: Volunteers were randomly assigned into the following treatment groups: Placebo (without F and TMP); 1100 ppm F (1100), 1100 supplemented with 3% micrometric TMP (1100 TMP) and with nano-sized TMP (1100 TMPnano). Volunteers were instructed to brush their natural teeth with the palatal appliances in the mouth during 1 minute (3 times/day), so that blocks were treated with natural slurries of toothpastes. After each phase, the percentage of surface hardness recovery (%SH_R), integrated recovery mineral loss (IML_R) and differential profile of integrated mineral loss (ΔIML) in enamel lesions were calculated. Data were analyzed by ANOVA and Student-Newman-Keuls test (p<0.05).
Results: The addition of micrometric TMP to fluoride toothpastes increased the %SH_R in 10% when compared with 1100 toothpaste (p<0.001). With nano-sized TMP, enamel surface became 20% harder than 1100 (p<0.001). In addition, the capacity to reduce the lesion body (IML_R) was ~ 43% higher with 1100 TMPnano compared with the 1100 (p<0.001). Also, 1100 TMPnano showed remineralizing capacity (IML_R; ΔIML) 66% higher when compared with 1100 TMP, with a more pronounced effect at deeper regions of the lesion (considering all the extension) (p<0.001).
Conclusions: It was concluded that the addition of 3% TMPnano to a conventional toothpaste was able to promote an additional remineralizing effect of artificial caries lesions.